The idea of system and repitition is portrayed in this film. In every setting and situation from the factory, the policemen to the jail everyone and everything is part of a controlled system. Even the seemingly chaotic protestors and the bustling dance floor of the cafe are systematic and ordered.
Charie Chaplin acts as a distruption to the strict ordered system. Everywhere he goes, he brings chaos and destruction. (The boat, the factory, the department store). The home that he lives in is rickety and falling apart and when he sings he ends up having to improvise the lyrics and dance. The scene in the department store where he is skating dangerously close to the edge of the flooring with a blindfold on is symbolic of his role as an agent of chance/chaos.
Charlie Chaplin has a moment where he considers surrendering to the systematic way of living when he considers the comforts of his jail cell to be better than being a free man, but that changes when he meets the girl. The girl, with no parents or authority figures, acts as someone that is completely free from any sort of system. She frees Charlie Chaplin from the trap of falling into a system and later he also rescues her from the policemen who try to capture her and put her into a foster home.
The movie is essentailly about escaping from the rigid systems of the city and society. The story is resolved in the end where Charlie Chaplin and the girl walk away from the city and leave behind all the rules and regulations that come with it.